Abstract: A floor surface treatment apparatus includes a wheeled vehicle having wheels and floor surface treating unit, and a dolly pivotally connected to the vehicle for pivoting movement between a lowered, support position in which the vehicle is supported by the dolly with the floor surface treating unit raised off the floor and a non-support position in which the vehicle is unsupported by the dolly. The dolly has at least three wheels for conjoint pivoting movement therewith relative to the floor surface treatment apparatus. The at least three wheels are arranged relative to each other such that in the support position of the dolly the at least three wheels stably support the apparatus with the floor surface treating unit raised off the floor. In its non-support position the dolly may be stowed onboard the apparatus during operation thereof.

Abstract: A mineral cutting pick of the type adapted to be traversed relative to a mineral face and having a leading cutting edge and an outer cutting edge incorporated in a hard metal insert mounted in a rebate formed by a pair of seating surfaces at the end of a pick body remote from a shank for use in securing in a socket of a chain or drum or the like, wherein at least one end of the leading cutting edge adjacent the outer cutting edge has negative rake with respect to the shank, and the leading cutting edge is defined by surfaces the angle between which increases from the position at which it will make foremost contact with the mineral face to the end of the leading cutting edge adjacent the outer cutting edge, whereby a sharper angle for the leading cutting edge is provided where it will attack the mineral face and a blunter angle is provided towards the end adjacent the outer cutting edge to afford greater strength as the insert decreases in transverse width towards the outer cutting edge.